Dot blot

It represents a simplification of the western blot method, with the exception that the proteins to be detected are not first separated by electrophoresis.

[3] A general dot blot protocol involves spotting 1–2 microliters of a samples onto a nitrocellulose or PVDF membrane and letting it air dry.

Samples can be in the form of tissue culture supernatants, blood serum, cell extracts, or other preparations.

Vacuum-assisted dot blot apparatus has been used to facilitate the rinsing and incubating process by using vacuum to extract the solution from underneath the membrane, which is assembled in between several layers of plates to ensure good seal between sample wells, hold waste solution, and deliver suction force.

For chemiluminescence signal detection, apparatus need to be disassembled and the membrane need to be taken out and wrapped in a transparent plastic film.

Typical dot blot membrane. Darker dots indicate more protein.